"We can't make enough of these things," Kessler said.
Combining the ball with the bat has also been a tremendous success. Kessler first sold it to Dick's Sporting Goods late last year and says he expects the company will sell 100,000 units in its 424 stores.
That's even despite a price point of $14.95, which might be considered risky since a Wiffle Ball with bat set has been sold forever at $4.99.
"The ball itself costs $10 and I couldn't justify giving people a crappy bat just to make it cheaper," Kessler said.
If there's any flaw to Kessler's product it's that replacement baseball-sized Sky Balls aren't sold separately (Wiffle balls come in a pack of nine for $10), so anyone who loses the Sky Ball has to buy the next biggest version, which is more like the size of a softball.
Kessler's father, Milton, didn't make a fortune off his Hula-Hoop patent because he abandoned production after 14 months in the late 50s to concentrate on his core business, manufacturing window and door parts in his factory in Youngstown, Ohio.
"It wasn't dumb at the time," Kessler said. "All he was doing was making Hula-Hoops and his regular customers needed their parts. It was during a huge construction boom."
Kessler never let it go and his Maui Toys decades later came up with a Hula-Hoop with water in it that makes it easier to twist and twist without it dropping to the ground. Kessler says his Wave Hoop makes up 65 percent of today's market.
The Sky Ball+Bat still has plenty of room to grow. After Dick's got the first crack, Toys R Us became its second vendor.
And Kessler isn't resting. Next year, he'll have the fat bat product for the four-year-old, who, thanks to the latest in ball technology, will be able to hit a Sky Ball 40 feet, Kessler says, with little more than a tap.
"It's time to bring the excitement back to sports," Kessler said.
And this one definitely brings it.
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